High-voltage structure



April 15, 1930. J. E. MATEER HIGH VOLTAGE STRUCTURE Filed May 19, 1927 2Sheets-Sheet -1 INVENTOR Jesse B. Mateer WITNESSES: #704,001?

ATTOR N EY April 15, 1930. 7 MATEER 1,754,833

7 HIGH VOLTAGE STRUCTURE Filed May 19, 1927 Q 2 Sheets-Sheet 2 inbreaker WITNIESSES: I INVENTOR M Z Jesse E. Maker ATTORNEY Patented Apr.15, 1930 UNITED STATES PATENT OFFICE JESSE E. .HATEER, OF WILKINSBURG,PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY,A CORPORATION OF PENNSYLVANIA HIGH-VOLTAGE STRUCTURE Application filedMay 19, 1927. Serial No. 192,589.

My invention relates to high-voltage structures and particularly tobushing structures and the associated parts of oil filled circuitinterrupters, or similar devices, with which the bushings areassociated.

One object of my invention is to provide a structure of theabove-indicated character that shall permit the bushing, as one unit,and a main casing or tank, a well structure for local disposition abouta portion of the bushing in the tank, and other parts, as another unit,to be adjusted relatively at, and shipped separately from, the factoryand assembled at the service station, without further adjustment.

Another object of my invention is to provide a bushing structure, for ahigh-voltage, oil-filled circuit interrupter, in which a body of oil,immediately adjacent to the bushing, shall be maintained free of carbonand metallic particles which are given off to the main oil body when theinterrupter operates under heavy loads.

Another object of my invention is to provide a well structure, forlocaldisposition about the inner end of a circuit-interrupter or similarbushing, that shall be adapted for insertion through the bushing openingin the interrupter tank and that shall permit the mounting of thebushing and of the well structure from the outside of the tank.

Another object of my invention is to, provide a well structure, for thereception of a bushing, in which a flexible conductor, for threadingthrough the bushing, shall be mounted for shipping with the well,separate- 1y from the bushing, and so fixed or adjusted at the factoryas to require no further adjusting and to preventits loosening by theeffects of current therein.

Another object of my invention is to provide an effectively sealedbushing structure that shall embody means for adjusting a conductor orcontact member, at one end thereof, relative to a cooperating conductoradjacent to said end, as by bodily adjusting the bushing relative to awall or cover member with which it is associated.

Another object of my invention isto provide a bushing structure thatshall so embody a condenser bushing and a surrounding well or oilcontained therefor as to Withstand very high voltages and to be, ingeneral, an improvement over bushing structures heretofore employed.

Another object of my invention is to provide a well structure, for ahigh-voltage bushing, that shall comprise a metal section and arelatively massive oil-immersed porcelain section having a creepagesurface of relatively great area, that shall be adapted for thereception of a transformer element and that shall embody effectivelysealed terminals for the transformer element.

A further object of my invention is to provide a high-voltage structurethat shall be simple and durable in construction, economical tomanufacture and effective in its operation.

In high-voltage structures, such as oil-filled circuit interrupters, thevarious parts must be exceedingly carefully designed, constructed,assembled, and adjusted because of the high-voltage stresses, thepresence of oil, the formation of gases and arcs, and other features.

Care must be taken, not only from a safety standpoint, but also that thedevice may always be in condition, when required to operate to a maximumdegree of efliciency and not be rendered ineffective from precedingoperations.

Since, in oil-filled circuit interrupters, the inner ends of theterminal bushings are usually immersed in the same body of oil thatsurrounds the contact members, carbon and metallic particles, which aresometimes formed when the interrupter operates under heavy loads, reducethe insulating value of the oil and tend to break down the surface ofthe bushing therein. The inner ends of such bushings are, also, usuallyprovided with limited or insufficient creepage surface. Also, by reasonof their size, certain of these interrupters and the bushings thereforare shipped separately and assembled at the place of installation.

Since the parts must be carefully put together at the factory,considerable trouble and expense are occasioned by the delicate andagain assembled.

Further, there is the .danger that the second, ,or final, assembly maynot be so carefully performed as the first assembly, with I theconsequent less effective operation and greater likelihood of damage.

It is my aim to reduce the above-mentioned effect of the carbon andmetallic'particlesin structure of their character to employ a condenserbushing that shall be entirely free of such particles, to provide adevice having materially increased creepage-surface area, and to providea structurein which the field mounting of the bushings shall be free ofdelicate adjustments and thereby rendered a simple and economicaloperation. 4

Accordingly, in practicing my invention, I provide a well structure forlocal disposition about the inner end of a bushing, that functions as abarrier between the oil next to the bushing and the main body of oil inan interrupter tank. The well structure and a. flexible conductor, forthreading through the bushing, are so assembled'and adjusted relative tothe tank and a movable contact member therein, and the bushing is soadaptready andeconomical mounting ofthe bush 7 ing during theinstallation of the interrupter,

without delicate adjustment or the require- 'ment of special skilL. .Thearrangement of parts is so improved as to provide amaterially increasedcreepage surface compared to structures heretofore employed.

I "Figure 1 of the accompanying drawings is a.view,'partially in sectionand partially in elevation, of a high-voltage structure embodying myinvention, and

Fig. 2 is a similar view of a modified form thereof 7 Referring to Fig.1, the device comprises, in general, a wall or cover member 2' of a tankor casing (not shown), a well structure 4, a current-transformer element5 in the well 4, and a' condenser-bushing structure 6.

The cover member 2, preferably constructedof metal, is provided with abushing opening 7 and can annular flange 9 is provided with aninwardly-sloping or beveled outer end edge. r w

" Therwell structure 4 comprises 'an"upp.er

or open-end metal section 12, a lower or 7 bottom insulating section 14,atop cover member 15 and a bottom structure 16. The metal section 12,preferably of relatively thin-walleduniform cylindrical shape,

comprises a laterally, outwardly-projecting upper flange -18, aninwardly-projecting lower flange 19 and a downwardly projectm lowerflange 20.

The upper flange 18 embodiesa sloping under surface 22 that socooperates the gasket 30 disposed over the top edge of thesections 12,has an opening 31, a flange 32-.

aboutthe opening 31, and an outwardly-anddownwardly extending outer-edgeportion 33. Bolts 34 extend through the portion 33 and into the flange18 for securing the well cover15 in sealed position.

The lower inwardly-projecting flange 19 provides a seat for thetransformer element 5 and an end shoulder for the upper end of theinsulating section 14.

The downwardly-projecting lower flange 20 is constructed to have aninner diameter substantially equal to the outer diameter of the mainbody portions thereof and to relatively closely embrace a portion of theupper end of the insulating section 14.

A sealing and securing medium, preferably of rubber compound, is placedbetween the flanges 19 and 20 and the adjacent surfaces of the section14. The insulating section 14 is preferably of relatively thick-walledand massive p'orc'elain construction, the side wall 35 of whichconverges downwardly and isprovided with surface-.creepage flanges 36.

Since all of the well structure 4, beneath the flange 18. isadapted forinsertion through the opening 7 in the cover 2, the top flange 36'is ofsmaller diameter than the opening 7 and projects only a certain distancefrom the main wall 3511f the section 14. However, by reason of thedownwardly-converging or tapering lar or sleeve portion 39 that issecured, as by r ,a body of cement 40, around the lower end of the wall35 and hasa bottom surface that. is preferably flush with the bottomsurface of the wall 35.

A metal plate 42, disposed flatly across the bottom end of the section14, is sealed and se cured thereto, as by a gasket 43 and screws 44,respectively.

A screw-threaded conducting stud element 46. which may be integral withor otherwise suitably secured to the plate 42, projects from the platefor the reception of a Stationary contact structure (not shown) of theinterrupter and has an opening at the inside of the plate for thereception of one end of a flexible condoctor or cable 48 which extends.through the bushing 6. .The cable 48, stud, 46, and plate 42 arepermanently connected to each other, as by welding, to resist thehighest mechanical and electrical stresses which are ordinarily met within service, without imparing the connection.

The current-transformer element 5, of which the cable 48 constitutes aone-turn primary Winding, comprises a laminated ring core member 50 anda secondary or low-voltstrengthening rib 75. It, also,

age winding 51 which closely conforms to the inner diameter ofthesection 12 and is. supported by the flange 19.

An oil-tight, low-voltage terminal device for the transformer 5comprises an insulating bushing 53, extending through the wall of thewell section 12, a conductor 54, extendin through the bushing, washers55 and nuts 5 for attaching adjacent conductors 58 and 59 in the circuitof the winding 51. The conductor 54 is preferably sealed in position inthe bushing 53, as by being molded in the material thereof or by beingsurrounded by a sleeve 60 of rubber compound or other suitable material.

The condenser-bushing structure 6 comprises an inner condenser member64, a metalcylinder supporting member 65, a collar member 67, aplurality of outer porcelain protective shells 68 and a to terminalstructure 70.

The condenser mem r 64 is preferably constructed of alternate layers ofmetal foil and hard, molded, fibrous, insulating material, such as paperimpregnated with a, phenolic condensation product, and is tapered orstepped, for considerable portions of its length, from the ends of auniform cylindrical mid-portion 71 to its outerextremities. Thisconstruction ensures a uniform voltage gradi-' ent between the cable 48and the cover member 2 and prevents undue concentration of electrostaticstresses.

The supporting cylinder 65 is sealed'to the mid portion 71 by a sealingmedium 73 and, sim larly to the metal well section 12, em-

dies an annular outwardly-extending flange 74 and a combined positioningand embodies a sloping upper surface 77 and is sealed and secured inposition on the flange 32 by a gasket 7 6 and screws .79, respectively,the latter of which extend into the well cover 15. V

The collar- 'member 67 embodies adongi- I tudinal cylindrical portion80, a sloping .under surface 82 for cooperation with the sealing gasket78 and the sloping upper surface 77, and alaterally-outwardly-projecting annular flange 85, for securing thecollar member 67 to the bushing-supporting member 65, by means ofbolts86 which extend between the flanges 74 and 85. t

The porcelain shells 68 have portions that are nested and cemented inposition, one within another, in a usual manner. A flange 87, of thebottom shell 68, rests on a sealin gasket 88 on a shoulder 89 in thecollar 6 and is secured in position in the cylindrical portion 80, by abody of cement 90. The upper shells '68 are smaller than the lowershells. by reason of the tapered upper end (not shown) of the condenserbushing member 64, and an insulating filling compound 92 is disposedbetween the shells 67 and the condenser member 64.

The stop terminal structure comprises a collar member 94 that is securedto the top shell 68, as by cementing and a member 95 having a laterallower flange 96 by which it is secured to the collar 94 by. means ofscrews 97. The member 95 further comprises liftinghook portions 99 and aterminal clip 100.

After placing the well structure in the opening 7, the stud 46, at thelower end thereof, may be moved laterally, to adjust the stationarycontact member thereof relative to the movable element of theinterrupter, as

above mentioned, by shifting the flange 18 on the flange 9, as in aball-and-socket Joint.

Since the distance frolnthe stud 46 to the flange 9 is relatively great,a very slight movement of the well structure, to change the angularposition of the longitudinal-axis thereof, effects a relatively greatadjustment of the stud 46. Slight adjustments of the latter are,therefore, almost imperceptible at the parts 9 and 18.

When it is desired to ship the entire structure, the condenser bushing6, with .its a-ppurtenant permanently attached parts, such as thecondenser member 64, the supporting cylinder 65,"the collar 67, theshells 68 and the top terminal structure 70 may be easily detached byremoving the screws 79.

In effecting the above detachment, the cable 48 is also detached fromthe top terminal structure 70 and allowed to fall into the -well 4, whenthe bushing i'sremoved. This feature is provided because the lower endof the cable must be securely fastened and is not sogaccessible in thefield where its top connection may easily be made.

Thus, the condenser bushing, with its attending parts, as one unit, andthe well structure with the cable 48 and the remaining interrupter partsas another unit, may conveniently be separately shipped for reassemblyinthe field without adjustment and dif- 'ficult connections. At theplace of installa? tion, the outer end of the slackened cable 48 isremoved from the well, the interrupter casing and the well are suppliedwith oil, the cable is threaded through the condenser member 64 andsecured to the terminal 70 and the well cover 15 is placed in position,all of which operations may easily and conture 4 is thoroughly sealed,

veniently be performed outside the interrupter casmg.

Since, as above described the well structhe oil-in the well and the oilin the interru ter casing, the levels ofwhich are represente by lines a:and y, respectively, are efiectively separated.

Thus, when carbon and metallic particles are given 011? by theinterrupter contact members when the latter are operated under heavyloads, and are suspended in the casing oil, the oil in the well ismaintained free thereof. This feature is important because any reductionof the insulating value of the oil along the tapered or stepped lowerportion of the condenser member 64, might result in breakdown of thebushing and damage to or del struction of the same and surroundingparts.

Further, since a space for gas must be maintained above the. main bodyof oil Y in the interrupter, the well structure 4 permits a higher levelof the oil X therein to be employed, thus providing a more eflectiveprotection of the condenser element 64 than if 'ular forms of myinvention,

wall member having a therethrough, a casing the well were not employed.

In the modification of my invention illustrated in Fig. 2, in whichcorresponding parts are designated by corresponding referencecharacters, the construction is substantially the same as that abovedescribed, except that the well structure 4 instead of being removablyand adjustably mounted on the cover member 2, is permanently fixedthereto, as by welding or brazing the metal section 12 thereof to thecover. member:

This construction prevents. adjustingthc stud-46, at the bottom of thewell, in the manner above described, but is a feature of economy overthe other construction;

Other slight differences in this form of my invention are that theflange 20, between-the metal section 12 and the insulating section 14 ofthe well, is a separate element, secured to the metal section by screws102, and the screws 34 extend into the cover member 2, instead of intothe well section 12.

While I have shown and described particchanges may be eflected thereinwithout departing from the spirit and scope thereof, as set forth in theappended claims.

claim as my invention:

1. A high-voltage structure comprising a bushing opening ofsubstantially cupshape embodying an insulatin rtion and disposed locallyabout the bus mg with its open-end perimeter secured to the wall memberaround said opening, a complete bushing unit having a portion 1n saidcasing and conducting means. extending through the bushing and thecasing.

2. A high-voltage structure comprising a Wall member having a bushingopening therethrough, a casing of substantially cupembodying insulatingand metal sections and disposed locally ing with its open end adjacentto the wall opposite said opening, said casing being suported solely bysaid wall member, a complete ushing unit having a portion insaid casing,and conducting means extending through the bushing and the casing.

3. A high-voltage structure comprising a wall member having an openingtherethrough, a local bushing well structure sealed to said wall memberopposite said opening and including a cover member, and a bushingextending through said cover member in sealed relation thereto at aposition adjacent thereto. 1

4. A high-voltage structure comprising a wall member having a bushingopemng therethrough and an annular flange projecting substantiallynormal to the wall around the opening, and means for receiving a portionof a complete bushing unit including a local bushin g well structurehaving a bottom portion insertable through said opening and alaterallyextending outer flange dis osed on said first flange in sealedrelations t ereto.

- 5. A high-voltage structure comprising a wall member having a bushingopening therethrough and a sloping seat portion around the opening and alocal bushing well structure that is independent of a complete bushingstructure which 'it is to receive and is disposed opposite said openingwith a portion cooperating with said sloping seat portion for angularlyadjusting the well structure relative to the wall member prior tothereception of the bushing structure.

6. A high-voltage structure comprising a wall member having a bushingopening therethrough and an annular flange projecting substantiallnormal to the wall around the opening em dying an inwardly-sloping seatportion, and a local bushing well structure having a bottom portioninsertable through said opening and a laterally-projecting outer flangecooperating with said resting the well structure on the wall member andan larlyadjusting the well relative to the wali said well structurebeing adapted for the reception of a portion of an independent andcomplete bushing-unit structure.

7. A high-voltage structure comprising a wall member having a bushinopening therethrough, a local bushing we the reception of a portion of acomplete bushing unit and secured to the wall member opposite saidopening and including means or conducting current through the wall ofthe well, and means for adjusting said conducting means relative to adevice outside the well with which it is to cooperate.

8. A high-voltage structure comprising a seat portion for.

structure for I cured to the wall member opposite said opening, means atthe bottom of the well for conducting current through the wall thereofincluding a conductor projecting from the hottom of the well, and meansfor adjusting said conductor angularly relative to the axis of saidopening.

high-voltage bushing structure comprising a wall member having a bushingopenng therethrough, a local bushing well struc ture secured to the wallopposite said opening, means for conducting current through the bottomof the well including a conductor for extension along the axis of thewell therein, and a complete bushing unit for insertion in the well oversaid conductor.

10. A high-voltage bushing structure comprising awall member havingabushing opening therethrough, a local bushing well structure secured tothe wall opposite said opening, means for conducting current through thebottom of the well including a flexible conductor in the well, and abushing for insertion in the well and having a central opening for thereception of said flexible conductor.

11.' A high-voltage structure comprising a wall member having a bushingopening therethrough, a local bushing well structure secured to the wallopposite said opening, a complete bushing unit having a portion in thewell, a transformer element disposed aroundsaid portion and a conductinglead for said element extending through the wall of the well in sealedrelation thereto.

12. A high-voltage structure comprising a fluid-containing casingincluding a metal cover member having an opening therethrough, a wellstructure comprlsing an upper metal section sealed to the cover memberaround said opening, a bottom insulating section sealed to said uppersection, a lid member for the well structure having an openingtherethrough, and a complete condenser bushing unit .supported in theopening in said lid member in sealed relation thereto adjacent thereto.

13. A high-voltage structure comprising a fluid-contaming casingincluding a metal cover member having an opening therethrough, a

well structure comprising an upper metal sec-. tion sealed to the-covermember around said opening, a bottom insulating section sealed to saidupper section, and having downwardly converging side walls, a lid memberfor the well structure having an opening therethrough, and a completecondenser bushing unit supported in the opening in said lid memher insealed relation thereto adjacent thereto, said bushing having a portionof substantially uniform relatively small diameter extending throughsaid upper metal section and a tapercd lower end portion in said bottominsulating section.

14. A-high-voltage structure comprising a fluid-containing casingincluding a metal covopening, a bottom insulating section sealed to isaid upper section, a lid member for the well structure having anopening therethrough, a complete condenser bushing unit extendingthrough the opening in the lid member and means on the bushing forsupporting the same on, and sealing the same to, said lid member.

15. In combination, a Wall member having a bushing opening therethrough,a bushing shield of substantially cup-shape extending transversely tosaid wall with its open end opposite said bushing opening, a completebushing unit having a portion for disposition in said shield, and meansfor supporting the shield and providing for the removal of said unitwhile said shield remains in place.

16. In combination, a well member having a bushing opening therethrough,a bushing shield of substantially cup-shape extending transversely tosaid wall with its open end opposite said bushing openin a completebushing unit-having a portion ibr disposition in said shield, and meansfor adjustably securing said shield in position and providing for theremoval ofsaid unit while said shield remains in place.

17. In combination, a wall member having a bushing opening therethrough,a bushing shield of substantially cup-shape extending transversely tosaid wall with its open end opposite said bushing opening, a completebushing unit disposed partially inside and partially outside saidshield, and means for closing said open end and supporting the bushinunit.

18. combination in a high-voltage circuit-interrupting device, a casinghaving a bushing opening, and an insulating element of substantiallycup-shape dis osed in the casing opposite said opening in ependent of.

to said wall with its open end secured thereto in position adjacent to,and in register with, said opening, and. a complete bushing unitremovably secured in position independently of the shield witha portionin said shield and a portion projecting from the opposite side of saidwall at which the bushing is disposed.

20. In combination, a wall member having an opening therethrough, ashield of substantially cup-shape extending transversely to said wallopposite said opening and having a laterally outwardly projectingportion removably secured to said wall at the side of the latteropposite to which the major portion of theshield is disposed, and acomplete bushing unitremovably secured in .pofition with a portion insaid shield and a portion proj therefrom.

Y 21. Incombination,in ahigh-voltage structure, a vessel for containinga fluid-immersed electrical device, a complete bushing unit extendingthrough a wall "of the vessel and means supported inde endentl oi, saidunit said se said opening and having a later ing portion adjacent to thewall for attachfor segregating said old from a 'fluid surrounding aportion of the bushing unit and providing for the removal of said unitwhile gating means remains in place. 22. 7' combination, a wall memberhaving an opening therethrough, a shield of substantially cup-shapeextendin transversely to said wall with its open end in re ister withy-extendment thereto, and a complete bushing unit removably secured-inposition with a portion in said shield and a portion projectingtherefrom.

23. In combination, a wall member having an opening therethrough, ashield of substantially cup-shape of smaller diameter than said openingextending transversely to said wall with its open end in register withsaid opening and having laterally-extending portlons adjacent to thewall for attachment thereto, and a'complete bushing'unit removablsecured in position with a portion in said s ield and a portionprojectin therefrom.

In testimony whereof: I have hereunto subscribed my name this 10th dayof May, 1927. i JESSE E. MATEER.

